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The first step of the scientific method is ____.Observe a phenomenon and ask a questionA(n) ___ is descriptive science; it describes natural structures and processes as accurately as possible through careful observation and analysis of dataTheory___ data are recorded observations, while ___ data are generally numeric recorded measurements.Qualitative, quantitativeScience uses ___ reasoning to formulate hypotheses, and ____ reasoning to analyze data and draw conclusions.Deductive, inductiveA hypothesis must be ____ and ____ in order to be valid and of use in studying a phenomenon.Testable, falsifiableTrue or false: All of the steps of the scientific method must be followed exactly in order with no backtracking or changes in order to test a hypothesisFalseA scientific theory is _____.
a.Something that is accepted as truth by the scientific community
b. Supported by many related hypothesis
c. Truth science builds upon when discovering new information about a natural phenomenon
d. All of the above
e. None of the aboveAll of the aboveTrue or false: Scientists publish their work so that other scientists can confirm it or refute it, and perhaps build upon itTrueOf the elements required for life; these make up 96% of living matter:Carbon, hydrogen, oxygen, nitrogenAtoms are made up of three subatomic particles. Which of these are those particles and their corresponding charges?Electrons (negative), protons (positive) and neutrons (neutral)A(n) ___ occurs when different atomic forms of the same element occur due to a difference in the number of neutrons each contains in the nucleus.Isotope____ is the capacity to do work; while ___ is the energy that matter possesses because of its location or structure.Energy, kinetic energyTrue or False: Chemical behavior of atoms depends on the number of electrons in the valance shell.TrueIn a(n) ___ bond, atoms share electrons in order to fill their valence shells; while in a(n) ___ bond, atoms are attracted to each other after the more electronegative atom strips the less electronegative atom of its valence electrons.Covalent, ionic___ covalent bonds are formed when electrons in the bond are attracted to the more electronegative atom and are not shared equally, thus creating areas of the molecule that are charged.PolarTrue or False: Ionic compounds are also called salts.True___ bonds are formed when a hydrogen atom covalently bonded to one electronegative atom is also attracted to another electronegative atom.Hydrogen___ occurs when hydrogen bonds hold separate water molecules together, and __ occurs when water molecules cling to other substances.Cohesion, adhesionTrue or False: Temperature is a measure of heat intensity that represents the average kinetic energy of molecules within a substance.TrueTrue or False: Water has a very low specific heat.FalseWhy does ice float?
a. Hydrogen bonds cause water molecules to lock into a crystalline lattice when it freezes
b. Ice is less dense than water
c. Ice is less dense due to the structure of hydrogen bonds
d. All of the above are correctd. All of the above are correct___ is a substance dissolved in a solution; while ___ is the substance that is the dissolving agent.Solute, solvent___ means water loving; these substances are ionic or polar molecules that can form hydrogen bonds.Hydrophilic___ are substances that increase the hydrogen ion concentration in a solution.Acids___ minimize the changes of pH in a solution by accepting hydrogens when they are in excess and donating hydrogens when they have been depleted.BuffersMost buffers contain ___.a weak acid and its corresponding baseTrue or False: Hydrocarbons are polar molecules.FalseGroups of atoms that participate in chemical reactions in a characteristic way are called ____.Functional groupsA ___ is a long molecule consisting of many similar or identical building blocks called ____.Polymer, monomersMonomers are connected through ___, and broken down through ___.Dehydration synthesis, hydrolysis___ include both sugars and polymers of sugars.carbohydrates___ are the major nutrients of cells, and are the monomers of carbohydrates.MonosaccharidesA ___ is two monosaccharides joined together by a bond called a ____.Disaccharide, glycosidic linkageWhen a polymer of monosaccharides is made up of a few hundred to a few thousand monosaccharides, it is called a ___.PolysaccharideTrue or false: Glycogen is used by plants to store surplus glucose.FalseTrue or false: The structural polysaccharide found in animals is chitin, while the one found in plants is cellulose.True___ is the most abundant organic compound on earth; is it a polymer of ____; and ____ be digested by many organisms (including humans).Cellulose, glucose, can notTrue or False: Lipids are true polymers and are usually large enough to be called macromolecules.FalseFats are constructed from a ___ and ____; they are ____ due this structure.Glycerol, fatty acids, nonpolar___ fats have no double bonds between carbons, are produced by ____, and are ____ at room temperature.Saturated, animals, solids___ is a common component of cell membranes, and is necessary for the production of human steroid hormonesCholesterolTrue or False: Proteins account for more than 50% of the dry mass of a cell and are instrumental in almost everything an organism doesTrueTrue or False: All amino acids have the same basic structure: an amino group, a carboxyl group, a hydrogen atom and an R-group.TrueAmino acids are joined by a covalent bond called a ____ bond.Peptide bondAt the ___ level of protein structure, amino acids are joined together; then at the ___ level of protein structure, folding of the polypeptide takes place due to hydrogen bonding along the R-groups.Primary, secondary___ occurs when a protein loses its shape due the breakage of hydrogen bonds.Denaturation___ give(s) the sequence of amino acids found in the production of a proteinGenesA nucleotide consists of ____.A nitrogenous base, a sugar, and a phosphate group___ is the semifluid, jelly like substance enclosed within the plasma membrane of a cell.CytosolA(n) ____ cell contains DNA enclosed in a nucleus bounded by a double membrane, while a(n)_____ cell contains no membrane-bound organelles.Eukaryotic, prokaryoticTrue or False: Examples of eukaryotic cells include plant and animal cells.TrueTrue or False: The plasma membrane is not selective in what it allows into and out of the cell.FalseThe nuclear membrane is ___.
a. A double membrane
b. Perforated by nuclear pores
c. Supported by the nuclear lamina
d. Both a and b
e. All of the aboveAll of the above___ consists of a complex of proteins and DNA found as long fibers.ChromatinTrue or False: Ribosomes may be free or bound.TrueThe endomembrane system:
a. Carries out a variety of tasks within the cell, including synthesizing proteins and carbohydrates
b. Includes the golgi apparatus, rough and smooth endoplasmic reticulum (ER), and the vacuoles
c. Includes the mitochondria and ribosomes
d. Both a and b
e. All of the aboveBoth a and bMembranous organelles within cells are either in direct contact with each other or use ____ to transport substances from one to another.VesiclesThe network of membranous tubules and sacs making up the ER are called ____.CisternaeTrue or false: The ER is continuous with the golgi apparatus.TrueSmooth ER:
a. Lacks ribosomes on its outer surface and synthesizes lipids
b. Detoxifies drugs and toxins and metabolizes carbohydrates
c. Stores calcium ions
d. All of the above
e. Both A and Bd. All of the aboveRough ER:
a. Has ribosomes on its outer surface and produces polypeptides
b. Finishes proteins for use both inside and outside of the cell
c. Produces membranes
d. All of the above
e. Both A and Bd. All of the aboveThe Golgi apparatus would be most extensive in cells used for ____.SecretionThe ___ face of the Golgi apparatus receives materials from the ____ and transports them through to the ___ face where they are placed in ____ for shipping.Cis, ER, Trans, vesicles___ vacuoles are formed by ____ while ___ vacuoles are used to pump excess water out of freshwater protists.Food, phagocytosis, contractileThe cytoskeleton is used for ____.
a. Mechanical support of the cell
b. Cell motility
c. Production of proteins
d. All of the above
e. Both A and Be. Both A and B___ are numerous and short and can move the environment past the cell or the cell through the environment, while ___ are long and few and move the cell through the environment.Cilia, flagellaThe ___ cell wall is the first secreted by the cell, it is followed by the ___ cell wall in some cells; ___ is the thick layer of polysaccharides found between the cell walls of adjacent cells.Primary, secondary, middle lamellaDesmosomes:Function like rivetsTight junctions:
a. Occur when the plasma membranes of adjacent cells are tightly pressed against each other
b. Form a continuous seal around and between the cells to prevent leakage
c. Prevent the leakage of extracellular fluid
d. Both A and B
e. All of the abovee. All of the abovePlasmodesmata:
a. Function like rivets to fasten cells together in strong sheets
b. Provide channels from one cell to an adjacent cell
c. Are used in communication between cells
d. Both B and C
e. All of the aboved. Both B and CCell membranes are:
a. Semi-permeable
b. Made up of mostly phospholipids
c. Contain proteins embedded and attached to them
d. Both A and C
e. All of the Abovee. All of the AboveCholesterol:
a. Is found in plasma membranes
b. Acts as a stabilizer by resisting freezing and by keeping the molecule from becoming too fluid at higher temperatures
c. Decreases the temperature at which the membrane solidifies
d. Both A and B
e. All of the abovee. All of the above___ proteins penetrate the hydrophobic core of the plasma membrane, while ___ proteins span the membrane.Integral, transmembraneThe major functions of membrane proteins include:
1. Transport
2. Enzymatic activity
3. Signal transduction
4. Cell-cell recognition
5. Intercellular joining
6. Attachment to the cytoskeleton1, 2, 3, 4, 5, 6___ are membrane carbohydrates bound to lipids.GlycolipidsTrue or False: Membranes do not have distinct inside and outside faces.FalseTrue or false: Non-polar molecules dissolve in the lipid bilayer of the plasma membrane and cross it easily.TrueTrue or False: Glucose, other sugars and water all pass through the plasma membrane very rapidly.False___ proteins function by having a hydrophilic channel that certain molecules or ions use as a tunnel to cross through the membrane; while ___ proteins hold onto the molecule they are transporting and change shape in order to shuttle it through the plasma membrane.Channel, transport__ is the movement of molecules from an area of high concentration to an area of low concentration.DiffusionTrue or False: Diffusion, osmosis, and facilitated diffusion are passive, while active transport, phagocytosis and pinocytosis require energy.TrueIf placed in a hypotonic environment, a cell will ____Gain waterWhen ___ occurs, the plasma membrane of plant cells pulls away from the cell wall due to a loss of water from within the cell.PlasmolysisTrue or false: Both facilitated diffusion and active transport use carrier proteins to move down a concentration gradient.FalseIon pumps:
a. Pump out ions against their concentration gradient
b. Establish an electrochemical gradient across the plasma membrane
c. Examples include the sodium-potassium pump and the proton pump
d. Both A and C
e. All of the abovee. All of the above__ occurs when a single ATP-powered pump transporting a specific solute indirectly drives the active transport of several other solutesCotransport___ occurs when cells take in large particles by extending pseudopodia around it and forming vacuole; ___ occurs when a cell wants to monitor the external environment.Phagocytosis, pinocytosis____ enables the cell to acquire bulk quantities of specific substances.Receptor-mediated endocytosis___ pathways release energy by breaking down complex molecules into simpler compounds.CatabolicIn living systems, potential energy is stored as _____.
a. Chemical energy
b. The bonds found in organic molecules
c. Fat
d. Glycogen in muscles
e. All of the abovee. All of the aboveIn a(n) ___ system, energy cannot be transferred between the system and its surrounds.ClosedTrue or false: A living organism is an example of a closed energy system.FalseTrue or False: The First Law of Thermodynamics states that energy cannot be created or destroyed, only transferred from one form to another.TrueTrue or False: The Second Law of Thermodynamics states that every energy transfer or transformation increases the entropy in the universe.TrueWhat is entropy?A tendency towards a more disordered systemIn order to decrease entropy and create _____, _______ must be used during the reaction.More order, energyCreating "More order" is equivalent to ____, while "less order" is equivalent to _____.An endergonic reaction, an exergonic reactionTrue or False: If the free energy change of a reaction is negative or zero, then the reaction will be spontaneous.False__ reactions proceed with a net gain of energy absorbed from the surroundings and store energy.EndergonicCells use ____, the use of an exergonic process to drive an endergonic one.Energy couplingEnzymes:
a. Are proteins
b. Lower the activation energy required to start a reaction
c. Bind to a substrate (or substrates) and convert the substrate(s) into the products of the reaction
d. All of the above
e. None of the aboved. All of the aboveEnzymes lower activation energy by:
a. Providing a template on which the substrates can come together in the proper orientation for a reaction to occur
b. Active sites stress and bend critical chemical bonds that must be broken for the reaction to occur
c. Provide a microenvironment conducive to a particular reaction type
d. Directly participate at the active site in the reactions
e. All of the abovee. All of the aboveEvery enzyme has an optimal _____ at which it operates.
a. Temperature
b. pH
c. both A and Bc. both A and BNon-protein enzyme helpers are called ____; if they are _____ they are called ____.b. Cofactors, organic molecules, coenzymesEnzyme inhibitors are necessary because ______.
a. They regulate the rate of enzymatic reactions
b. They control the amount of product produced
c. Both A and Bc. Both A and B______ enzyme inhibitors mimic normal substrate to regulate reactions, while _____ impede reactions by binding to a part of the enzyme other than the active site to change its shape.Competitive, noncompetitiveTrue or False: Allosteric regulation occurs when a protein's function at one site is affected by the binding of a regulatory molecule to a separate site.TrueIn allosteric regulation, a(n)____ stabilizes the active sites of enzymes to ______ a reaction, while a(n) ____ stabilizes an inactive shape of enzymes to ______ a reaction.Promoter, promote, inhibitor, preventMicrofilamentsO. solid rods made up of actinVacuoleJ. large membrane-bound vesiclesNucleusD. contains the genetic material of the cellCell wallP. protects, maintains shape, prevents excessive uptake of water in plant cellsNucleolusE. where ribosomal RNA is producedRough endoplasmic reticulumF. extensive network of membranes with ribosomes attachedRibosomesC. made up of rRNA and proteins; produce proteinsChloroplastL. site of photosynthesisSmooth endoplasmic reticulumG. extensive network of membranes that synthesize lipidsGolgi apparatusH. center of manufacturing, finishing, warehousing and storage of productsChromosomesB. carry genes in the form of DNAPeroxisomeM. single-membrane sacs containing enzymes that produce hydrogen peroxideMitochondriaK. site of cellular respirationPlasma membraneA. the selective membrane that surrounds the cellMicrotubulesN. hollow rods made up of tubulinLysosomeI. membranous sac of hydrolytic enzymes____ pathways release energy by breaking down complex molecules into simpler compounds.CatabolicTrue or False: Cells degrade complex organic molecules that are rich in potential energy to simpler waste products that have less energyTrueWhen cells harvest energy from organic molecules, the energy is ___.
a. Used to do cellular work
b. Lost as heat
c. Stored
d. Both a and bd. Both a and b___ is the most prevalent and efficient catabolic pathway.Aerobic respirationTrue or False: The term "cellular respiration" includes both anaerobic and aerobic respiration.TrueThe chemical equation for aerobic cellular respiration (in words) is: Glucose + _____ à carbon dioxide + _____ + energyOxygen, waterTrue or false: The breakdown of glucose in cells is an endergonic reactionFalseIn a redox reaction, one molecule is ___, and then another molecule is ____.Oxidized, reducedThe more electronegative an atom, the more ____ required to take an electron away from it.EnergyOrganic molecules that have an abundance of ___ are excellent fuels because their bonds are a source of electrons whose energy may be released as they fall down an energy gradient.HydrogenWhich of the following molecules are/act as electron carriers during aerobic respiration?NAD+ and FADDuring glycolysis:Glucose is broken into two pyruvate moleculesDuring the Electron Transport Chain:Hydrogens are combined with oxygen and release energyTrue or False: Glycolysis takes place in the cytosol, the Citric Acid cycle takes place in the mitochondrial matrix, and the Electron Transport Chain occurs in the inner membrane of the mitochondria.TrueThe net energy yield per glucose molecule during glycolysis is ___2 ATP + 2 NADHDuring the citric acid cycle:
a. Pyruvate is converted to acetyl coenzyme A and CO2
b. Electrons are stored as NADH
c. Electrons are stored as FADH2
d. 3 NADH, 1 FADH2 and 1 ATP are produced
e. All of the abovee. All of the aboveThe electron carriers take ____ to the Electron Transport Chain, where they will be used to generate energy in a series of ___ reactions.Hydrogens and electrons, redoxThe Electron Transport Chain is ____A collection of molecules embedded in the inner membrane of the mitochondrion in eukaryotic cells and the plasma membrane of prokaryotic cellsTrue or false: Most components of the Electron Transport Chain are proteins.TrueWhat happens during the Electron transport chain?
a. Electron carriers alternate between reduced an oxidized states as the accept and donate electrons
b. Carriers are reduced as the accept more energetic electrons and oxidized as they lose less energetic electrons
c. The energy change in electrons results in energy harvested for cellular use
d. The energy lost is used to produce ATP via oxidative chemiosmosis
e. All of the abovee. All of the aboveWhat is used as the final electron acceptor in the Electron Transport Chain?Oxygen___ couples the energy released by the Electron Transport Chain to the production of ATP.ChemiosmosisTo produce ATP, the following must occur:
a. Hydrogen ions are pumped across the mitochondrial membrane to establish a gradient so they will flow through ATP synthase channels while trying to reach equilibrium
b. As the hydrogen ions flow through the channels, molecular rotors turn and produce ATP
c. Water must be split
d. Both a and b
e. All of the aboved. Both a and bWhere does the energy for the pumping of hydrogen ions against their concentration gradient come from?d. The exergonic flow of electrons from NADH and FADH2What is the total amount of ATP produced via aerobic cellular respiration?32-34True or False: Anaerobic respiration takes place in certain prokaryotic organisms and does use an Electron Transport Chain, but oxygen is not the final electron acceptor.TrueTrue or False: Fermentation does not use and Electron Transport Chain or oxygen.True___ anaerobes can make enough ATP to survive using either fermentation or aerobic respiration.FacultativeWhat other molecules can be used by cells during cellular respiration to make ATP?
a. Fats and starch
b. Proteins
c. Sucrose and proteins
d. All of the aboved. All of the aboveFood provides us directly with____.
a. Fuel for cellular respiration
b. Building blocks for the body
c. ATP
d. Both a and b
e. All of the aboved. Both a and b___ produce organic molecules from carbon dioxide and other inorganic raw materials.Autotrophs___ use sunlight as a source of energy for the production of organic molecules.PhotoautotrophsThe equation for photosynthesis is: ___ + 12H2O + ___ -> C6H12O6 +6O2 + 6H2O6CO2, light energyTrue or False: The oxygen given off from photosynthesis comes from the splitting of carbon dioxide.FalseTrue or False: During photosynthesis, water is split, electrons and hydrogen ions are then transferred from water to carbon dioxide, thus reducing it to sugar.TrueTrue or False: During photosynthesis, electrons increase in potential energy as they move from water to sugar, so the process requires and input of energy from sugar.FalseDuring the Light Reactions of photosynthesis:
a. Solar energy is converted to chemical energy
b. Water is split, providing hydrogen ions and electrons and giving off oxygen as a by-product
c. Light absorbed by chlorophyll drives the transfer of electrons and hydrogen ions from water to electron carriers
d. ATP is generated
e. All of the abovee. all of the aboveDuring the Calvin Cycle:
a. Carbon dioxide from the air is incorporated into organic compounds in the chloroplasts
b. Fixed carbon is reduced to carbohydrate by the addition of electrons using ATP
c. ATP is produced in the thalykoids
d. Both a and b
e. All of the aboved. Both a and bDiscrete particles of light are called ___.Photons___ are substances that absorb visible light.PigmentsThe colors reflected back by an object are the wavelengths of light that ____ absorbed by the pigments the object contains.are notChlorophyll ___.
a. Is made up of two pigments, chlorophyll a and chlorophyll b
b. Is green
c. Absorbs all colors of light but green
d. Both a and b
e. All of the abovee. All of the above___ are accessory pigments used to absorb more light in the leaf and to photoprotect the leaf; they are ___Carotenoids, various shades of yellow and orangeWhen a molecule of chlorophyll absorbs a photon of light, what happens?
a. One of the molecule's electrons is elevated to an orbital where it has more potential energy
b. One of the molecule's electrons is excited
c. One of the molecule's electrons now has more potential energy
d. All of the aboved. All of the aboveTrue or False: Excited electrons are stable.FalseA photosystem includes:
a. A protein complex called a reaction-center complex
b. Several light-harvesting complexes
c. A special pair of chlorophyll a molecules
d. All of the aboved. All of the aboveA light-harvesting complex is made up of___, and a reaction-center complex is made up of___.Various pigment molecules bound to proteins, molecules capable of accepting electrons and becoming reducedTrue or False: ATP is produced during the Light reaction by establishing a proton gradient and ATP synthase channelsTrueThe end result of the Light reaction is:
a. The use of solar energy to produce ATP and NADPH
b. The provision of chemical energy and reducing power to the Calvin Cycle
c. The production of carbohydrates
d. Both a and b
e. All of the aboved. Both a and bTrue or False: C4 and CAM plants use alternative methods of carbon fixation because they must keep their stomata closed or partially closed due to the hot climates they inhabit.TruePut the following steps in the order in which they occur during the Calvin Cycle of photosynthesis:
Regeneration: the CO2 acceptor is regenerated using three molecules of ATP
Carbon fixation: each CO2 molecule is attached to a five-carbon sugar molecule forming a 6-carbon intermediate that immediately splits in two
Reduction: each 3-carbon molecule receives an additional phosphate group from ATP, then a pair of electrons from NADPH, transforming it into the 3-carbon sugar that exits the cycleRegeneration: 3
Carbon Fixation: 1
Reduction: 2An enzyme catalyzes the splitting of a water molecule into two electrons, two hydrogen ions, and an oxygen atom; oxygen gas is formedStep 3Photoexcited electrons are passed in a series of redox reactions from the primary electron acceptors of PSI down a second electron transport chainStep 7Light energy is transferred to the PS I reaction-center complexStep 6Each photoexcited electron passes from the primary electron acceptor of PS II to PS I through an electron transport chainStep 4A photon strikes a pigment molecule in a light-harvesting complexStep 1The electron is transferred from the excited pigment to a primary electron acceptorStep 2Energy is harvested from the electron transport chain and is used to synthesize ATPStep 5NAD+ picks up hydrogens, forming NADPH; these will be used in the Calvin CycleStep 8True or False: Cell division only occurs when an organism is growing.False____ is the life of a cell from the time it is first formed from a dividing parent cell until it divides.The cell cycleTrue or False: Cells must distribute DNA when they divide in order to produce living cells.TrueAll of the genetic information in a cell is called the ____, which is made up of units of genetic material called _____.Genome, chromosomes____ code for a specific genetic trait, while ____ code for different forms of that trait.A. Genes, allelesMost of a cell's life is spent in what part of the cell cycle?InterphaseDuring which stage of the cell cycle are the chromosomes duplicated?SThe G1, S, and G2 phases of the cell cycle are collectively known as:InterphaseDNA wraps around histone proteins before cell division takes place - this forms ___ from ___.chromosomes, chromatinReplicate copies of each chromosome are called ____ and are joined at the __.sister chromatids; centromereMitosis is:the division of the nucleusThe proper sequence, beginning to end, of the stages of mitosis is:Prophase-Prometaphase-Metaphase-Anaphase-TelophaseThe eukaryotic cell cycle is controlled at several points; which of these is not a checkpoint?
A. growth is assessed at the G1 check point
B. DNA replication is assessed at the G2 check point
C. Mitosis is assessed at the M check point
D. All of these are control points of the cell cycleD. All of these are control points of the cell cycleDuring mitosis, the ___ forms in the cytoplasm during prophase; it consists of ___.spindle, microtubuleThe spindle is created as the ____ replicates and moves to opposite poles of the cell.CentrosomeThe ___ is the structure of proteins associated with the sister chromatids at the region of the centromere; its function is to ____.kinetochore, attach the chromosomes to the spindle fibersThe daughter chromatids are separated and pulled to opposite poles during ___ of mitosis.AnaphaseDuring ___, the division of the cytoplasm and organelles will occur.cytokinesisAn animal cell forms a ___ during cytokinesis, while a plant cell forms a ___cleavage furrow, cell plateCells activate certain genes to specialize for certain functions in a process called ___.differentiationTrue or False: Bacterial cells undergo mitosisFalse____ is the transmission of genetic traits from one generation to the next.HereditaryTrue or False: Offspring are not identical copies of their parents due to genetic variation.TrueThe diploid number of chromosomes in humans is 46. The haploid number is:23True or False: All living organisms have the same number of chromosomes.FalseSex cells are also called ___.gametesGametes are ___, while somatic cells are ___.haploid, diploidThe union of an egg and a sperm (fertilization) results in:
A. A zygote
B. A diploid cell
C. A cell with a new genetic combination different than that of the parents
D. All of these are correctD. All of these are correctIdentical pairs of chromosomes that have the same genes at the same locations (code for the same traits) are called ___Homologous chromosomesTrue or False: Sex chromosomes (X and Y) are truly homologous chromosomes.FalseTrue or False: All sexual life cycles are the sameFalseThe process by which a diploid cell is divided to produce haploid cells is called ___.MeiosisMeiosis allows for sexual reproduction, which is significant because ___.
A. it produces unique individuals
B. it introduces genetic variability
C. it brings about different genetic combinations than found in the parents
D. all of the aboveD. all of the aboveDuring Prophase I, homologous pairs form ___.bivalents/tetradsDuring meiosis, replication of DNA occurs:During interphaseThe exchange of DNA segments while the homologous pairs are synapsed is called ___.crossing-overCrossing over occurs during ____.Prophase IDuring Metaphase I, ___ takes place due to the random arrangement of homologous pairsindependent assortmentWhen does separation of homologous chromosomes occur during meiosis?Anaphase IThe separation of homologous pairs is called a ___ because it ___.reduction division, reduces the number of chromosomes by half (separates the homologous pairs)Genetic recombination is possible because of ____during or after meiosis.
A. Independent assortment
B. Crossing over
C. Fertilization with a gamete from another person
D. All of these are correctD. All of these are correctThere are over 8.4 million diploid combinations of alleles in a mother and father without considering crossing over; ______ increases this to over 70 trillion different possible diploid combinations (still without considering crossover).Random fertilizationWhich of these is not a unique feature of meiosis?diploid daughter cellsMitosis results in two diploid cells, while meiosis results in four ____ gametes.HaploidWhen an individual's unique set of alleles allows for better survival and reproduction, which causes the alleles to persist in the population, _____ has occurred.Natural selectionThe nuclear envelope fragments, the kinetichore attaches to the spindle fibersPrometaphaseEach set of chromosomes is now at opposite ends of the cell, they become enclosed in a nuclear membrane; the nucleoli reappear, the chromosomes unravel, and cytokinesis occursTelophaseChromatin fibers condense into chromosomes, the centrosomes move to opposite poles, the mitotic spindle forms. The nucleoli disappear.ProphaseCohesion proteins are cleaved, sister chromatids pull apart as the centromere divides, and the daughter chromosomes start to move toward opposite ends of the cell via the spindleAnaphaseSister chromatids align at the equatorial plane; their kinetochores attach to the spindle fibers.MetaphaseGregor Mendel's work was different from that of other researchers working on inheritance in his day because he alone:Actually counted the numbers and types of offspring and analyzed them statisticallyTwo true-breeding pea plants are crossed, one with purple flowers and the other with white. Their offspring are:Heterozygous with the dominant phenotypeWhen two parents are crossed, the offspring are referred to as the:F1 Generation___ are alternate forms of genes.alleles___ is the alleles present in an organism, while ___ is the physical expression of those alleles.Genotype, phenotypeA ___ cross examines one trait at a time.MonohybridTall is dominant to short in pea plants. If two short pea plants were crossed, their offspring will be:All short plantsWhen you have two identical alleles for a trait, you are said to be ___ for that trait.homozygousIn order for a recessive trait to be expressed, you must be ___ for that trait.homozygousThe degree of earlobe attachment in humans is said to be free or attached. Free earlobes are dominant over attached earlobes. What is the probability that the children of a woman with attached earlobes will have attached earlobes if their father has free earlobes, but his father had attached earlobes?50%In snapdragons, pink-flowered plants are produced when red-flowered plants and crossed with white-flowered plants. This type of inheritance can best be described as:Incomplete dominanceIn the human ABO blood grouping, there are four basic blood types, type A, type B, type AB, and type O. The blood proteins A and B are:CodominantWhat does codominant mean?both alleles are not changed and are expressed to their full extent in the presence of each otherWhen a trait is governed by two or more sets of alleles, it is said to be ___.polygenicIf a gene has a variety of effects on the phenotype of an organism, it is said to be ___.pleiotropicSiamese and Himalayan cats (and some foxes and rabbits) have genes that produce enzymes that are heat-sensitive, causing a seasonal variation in coat color due to:An environmental effectMendel's Law of ___ states that when gametes are formed by a diploid organism, the alleles that control a trait separate from one another into different gametes, retaining their individuality.SegregationGenes for sex-linked traits tend to be carried on what chromosomes?X chromosomeRed-green colorblindness is a sex-linked trait. A woman with normal color vision, whose father was colorblind, mates with a colorblind man. What chance does each of their sons have being colorblind?50% chanceHumans who have lost one copy of a chromosome have a ___ and generally do not survive development.monosomyWhen homologous chromosomes are chromatids fail to separate properly in meiosis, this is called ______________.NondisjunctionA DNA nucleotide is composed of:A deoxyribose sugar, a phosphate group, and a nitrogenous baseThe nitrogenous bases found in DNA are:Adenine, thymine, guanine and cytosineIn RNA, the nitrogenous base ___ is substituted for ____.Uracil, thymineIn complementary base pairing in DNA, which bases always pair together?A with T and C with GWhen DNA replicates, each original strand of DNA serves as a template for a new strand. This is called ____.Semiconservative replicationDNA replication begins at:Origins of replicationDNA attachments are broken by ____ so the two strands of DNA can be untwisted.DNA helicaseWhen the two halves of DNA are unzipped, a _____ is formed.Replication bubbleAt the end of the replication bubble is a ____, a region where the parental strands of DNA are being unwound.Replication forkAfter parental strand separation, ____ stabilize the unpaired DNA strands to keep them from rejoining.Single-strand binding proteinsThe role of topoisomerase is to:
A. Keep the DNA from twisting too tightly as it is unzipped
B. Break, swivel and rejoin the DNA strands to reduce tension
C. Both a and bBoth a and b___ brings new complementary nucleotides in and binds them to the old strand of DNADNA polymeraseTrue or False: The DNA strands elongate in opposite directions, as bases can only be added to the 3'end of the DNA strand.True___ joins the Okazaki fragments together.DNA ligaseThe new DNA strands are proofread and will be corrected if necessary by ____.
A. DNA polymerase
B. DNA helicase
C. Correction enzymes
D. Both A and CD. Both A and CA permanent change in the sequence of bases in a gene is called a(n) ___.Mutation___ are special nucleotide sequences on the 5'ends of DNA stands that protect genes from being "worn off"TelomeresIt is hypothesized that the shortening of telomeres is associated with:
A. Aging
B. Cancer protection
C. Mutations
D. Both A and BD. Both A and BTrue or False: Genes do not directly control the production of proteins, they pass on their information to RNA and RNA controls the production of proteins.True___ is the process of transcribing the DNA code into mRNA, while ___ is the process of translating the DNA language into amino acid language as proteins are made.Transcription, translationThe genetic code used to indicate a particular amino acid in a DNA molecule is a sequence of ___ bases, and is called a ___.3, tripletA ___ is a sequence of ___ bases on mRNA that codes for a particular amino acid.Codon, 3Put the steps of transcription in order:
1. The termination code is reached
2. DNA is unzipped at the promoter region by RNA polymerase
3. RNA polymerase moves along the DNA, untwisting and exposing bases
4. RNA polymerase binds and transcription begins,
5. An enzyme checks to make no mistakes are made2,4,3,5,1___ are meaningless sections of DNA that are excised out of mRNA before proteins are made.IntronsTrue or False: There is at least one tRNA molecule for each of the 20 amino acids found in cells.TruetRNA has a sequence of ___ bases called a ____, that is ____ to the sequence of bases on the mRNA.3, anticodon, complementaryTranslation takes place in the ___.RibosomeRibosomes have ___ for both mRNA and tRNA to bring the two molecules together; this allows ___.Binding sites, peptide bonds to form between amino acidsA single base-pair change in the sequence of DNA bases is called a ___.Point mutation___ mutations have no effect on the encoded protein due to the redundancy of the genetic code.SilentGiven the following sequence of bases in a DNA molecule, what would the corresponding sequences be if this DNA molecule were replicated?
A A G G A A
T T C C T T
A. T T C C T T
A A G G A A
B. U U C C U U
T T G G T T
C. A A G G A A
T T C C T T
D. Either A or CD. Either A or CGiven the following template strand (coding strand) of DNA, what is the complementary stand of mRNA, and what are the corresponding tRNA molecules?
A A G G A A T T CmRNA: U U C C U U A A G
tRNA: AAG GAA UUC
